1. Field of the Invention
The present invention relates to a method for reducing the amount of NO.sub.x, and for raising the output, of a gas turbine power station of the type utilising an air reservoir, and a gas turbine power station, of this type, operating in accordance with this method.
2. Description of the Prior Art
For the production of compressed air at a high pressure, such as for example, in the case of gas turbine power stations of the type utilising air reservoirs, two or more compressors are customarily connected in series, the air being led between each two compressors through ihtercoolers and, after the last compressor, through an aftercooler in order to reduce the compressor drive-power and to reduce the volume of the air. Since the air is drawn in from the open environment, it always contains water vapour. If the air temperature remains constant, the amount of water separated out in liquid form increases with rising pressure. For example, at 50 bar final pressure and 20.degree. C., the air retains, in vapour form, only 1/50 of the maximum water content which it can absorb at ambient pressure. At such a high compression, virtually the whole of the water vapour which is drawn in from the environment with the air, thus condenses in the intercoolers and in the aftercooler.
In order to avoid disturbances in the machines and apparatuses, this condensate must be removed from the compressor-circuit by water separators. In the case of a compressor which, for example, draws in 300 kg of air per second at 20.degree. C. and 80% relative humidity, 12.5 m.sup.3 of water are produced per hour, as the result of this separation process, which is led away unused by means of a water-removal system. The quality of this condensate approximates that of rainwater.